Machine for making concrete blocks.



K E, lz vlm F. B. WILLIAMS.

MACHINE FOR MAKING CONCRETE BLOCKS.

APPLICATION FILED MAE.7.1910.

Patented Sept. 26, 1911.

9i 3 D H M F. B. WILLIAMS.

MACHINE FOR MAKING CONCRETE BLOCKS.

APPLICATION FILED MAR. 7, 1910.

1,004, 327. Patented Sept. 26, 1911.

2 SHEETS-SHEET 2.

i H r 12 -i1z v'1 W aw W UNITED STATES PATENT OFFICE.

FRANK B. WILLIAMS, 0F CAMBRIDGE, MASSACHUSETTS, ASSIGNOR OF ONE HALF TO CHARLES J. OUELLET, OF CAMBRIDGE, MASSACHUSETTS.

MACHINE FOR MAKING CONCRETE BLOCKS.

Specification 01' Letters Patent.

Patented Sept. 26, 1911.

To all whom it may concern:

Be it known that I, FRANK B. WILLIAMS, a citizen of the United States, residing at Cambridge, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Machines for Making Concrete Blocks, of which the following is a specification, reference being had therein to the accompanying drawin My invention relates to machines f o r making concrete blocks and the like.

In the manufacture of concrete blocks it is essential that suitable forms or molds be provided to receive the concrete while in a plastic state and to form and to hold the blocks intact until they have dried sufiiciently to permit the removal of the forms. There are three well known methods employed and these methods vary as to the consistency of the concrete when molded and the treatment of the concrete while in the forms. One of these methods consists. in mixing a concrete which is comparatively dry, filling the form with successlve layers and tamping each layer in turn to condense the mass. When finished the form is removed and the block allowed to dry gradually. From time to time during the drying process the block is sprinkled with water to facilitate the setting of the cement in the concrete. This process is open to the objection that the tamping of the concrete in successive layers causes lines of cleavage to be formed throughout the block and it is thereby greatly weakened and liable to split on these lines of cleavage when subjected to strain. Another method consists in using concrete comparatively dry and then subjecting it to pressure when in the form or mold. The resulting block, however, is not of uniform density for the pressure causes the outer portions to be compressed to a greater degree than the inner parts. The third method has been to fill the mold with a liquid concrete and to allow it to dry and set in the mold. This method gives the best result for the blocks are of uniform and even structure, homogeneous and without lines of cleavage but it is expensive. The blocks must remain in the molds for a day or two and to manufacture any considerable number of blocks requires an immense number of expensive molds.

The object of my invention is to provide a machine of simple construction for making concrete blocks of uniform density and free from lines ofcleavage.

A further object is to .do away with a multiplicity of forms or molds and thereby reduce the cost of the blocks.

A third object is to secure a machine which may be operated efiiciently and rapidly.

Briefly my invention resides in a machine consisting of a suitable frame, a molding box supported on said frame and means for raising said molding box and dropping it on said frame in rapid succession to cause the concrete in the molding box to be settled or condensed uniformly.

In the accompanying drawings illustrating the preferred embodiment of my invention, Figure 1. is a side elevation of the machine a portion of one side of the mold ing box bein broken away to show the interior thereo and Fig. 2 is an end elevation of the machine, the dotted lines showing the position of the molding box when raised divided into various compartments to permit a plurality of blocks to be molded at one time. The molding box shown in the drawings is divided into four compartments by a central longitudinal partition 5 and a central transverse partition 6. Within the molding box is a false bottom or pallet 8 upon which the concrete blocks rest and to facilitate the removal of the pallet and the blocks from the molding box after the blocks have been formed, transverse strips ,9 are interposed between the base 4 and the pallet 8. The sides 2 and ends 3 of the molding box are connected by hinges 10 or in any other suitable manner to the base 4: to allow the box to be opened by swinging the sides and ends outwardly and downwardly. When closed as illustrated, the sides and ends are held together by hasps 12. The

sides 2 are strengthened by reinforcing strips 13.

Around the top edges of the molding box fits a hopper 14 which is supported by brackets 15 mounted on the sides and ends of the molding box and is secured in lace by pins 11. The hopper serves as additional means to retain the sides and ends in a closed position. The main purposes of the hopper 14, are, however, to facilitate the loading of the molding box with concrete and to allow the concrete to be heaped up above the top edges of the said box. As the machine is operated the concrete settles and unless an excess amount of concrete is placed in the beginning of the operation, it will be necessary to add further concrete to make up the loss due to the settlin This would require stopping the machine 1n the midst of the operation and might result in a line of cleavage in the finished block. The hopper obviates this difliculty and any excess of concrete can be scraped from the top of the molding box after the operation of forming the blocks is finished and the hopper removed.

To raise the molding box and drop it in rapid succession, I provide the following means. the molding box and centrally located, are depending racks 16 which mesh with segment pinions 17 mounted on a shaft 18 extending lengthwise of the machine and supported in hangers 19. At one end the shaft 18 is rovided with a fixed arm 20 and when this arm is turned, the shaft and segment pinions are rotated and the racks and the molding box reciprocated. Rotatably mounted at the same end of the machine as the arm 20 on a shaft 21 is a gear-wheel 22. The shaft 21 is arranged on one side of and slightly below the shaft 18 and is supported at one end by the frame 1 and at the other and outer end by a bracket 23 secured to the frame 1. The gear wheel 22 is provided on its inner side adjacent to its circumference with a plurality of laterally projecting pins or rolls 24 arranged at equal intervals and the gear wheel is so arranged with reference to the arm 20 that when the former is rotated one of the pins or rolls 24 strikes the arm 20 and carries it downwardly thereby turning the shaft 18. Owing 'to the facts thatthe gear-wheel is mounted eccentrically with respect to the shaft 18 and that the arm 20 is of a specified length, the particular roll 24 which happens to be in contact with the arm 20 slips off the arm when it reaches a lowermost position thereby releasing the arm and permitting it to swing back to be can ht by the next succeeding roll or pin. T e turning of the arm 20 as above described, rotates the shaft 18 through the medium of the segment pinions 17 and racks 16 and raises the Secured to the bottom or base 4 of molding box. When the pin 24 slips ofi' the end of the arm 20 the latter is released and the molding box drops causing the shaft 18 to be turned back and the arm 20 returning to a normal horizontal osition to be caught by the succeeding rol or pin. The gear wheel 22 is turned by a pinion 26 mounted on a small shaft 27 supported in hangers 28. In the drawings the machine is shown as operated by hand, the pinion being turned by a hand lever 30 but the machine may be operated by power if desired.

The molding box is also provided with depending guides 32 passing between rolls 33 in the top of the frame to obviate lateral movement as the molding box reciprocates.

In order to adjust the force of the blow received by the molding box as it falls on the frame, a series of coiled springs 34 supported by plates 36 on hangers 38 are arranged on the frame 1 under the molding box. The hangers 38 are screw threaded at their lower ends and nuts-39 are provided by the adjustment of which the springs may be raised to break the fall of the molding box. These springs are not, however, an essential feature of the invention and may be omitted if preferred, as it is possible to regulate the drop of the molding box by increasing or diminishing the length of the arm 20. The height to which the molding box is raised before it is dropped depends upon how far the arm 20 is carried by the pins 24 and if the arm is shortened or lengthened the amount of the drop is correspondingly decreased or increased.

In the use of the machine, the concrete is prepared in a partially dry state; that is, with suflicient water to give it the consistency of moist sand in order that it will retain its form when removed from the molding box. The molding box is then entirely filled with the concrete which is heaped up to a level with the top of the hopper. The hand lever 30 is then turned thus rotating the gear-wheel by means of the pinion 26. As the gear-wheel rotates, a pin 24 contacts the arm 20 carrying it downwardly and turning the shaft 18 and segment pinions 17 and raisin the racks 16 and the molding box. Owing to the pivotal location of said arm 20 the pin 24 slides along the arm as it is turned and finally slips off the end. The arm is thereby released and the molding box falls on the frame returning the racks, segment pinions and arm to their normal position. The next pin then catches the arm and repeats the operation. The effect of these repeated shocks is to cause the concrete in the moldi box to be condensed and compacted and a er the machine has been operated a short time, the hopper is removed, the surplusconcrete removed and the blocks leveled. The ends box, the sides and ends closed and fastened,

the hopper readjusted and the machine is ready to be again filled with concrete.

It is to be observed that by the use of this machine concrete blocks can be molded with on one end of said shaft whereby said shaft great rapidity and with very little ex ense.

It dispenses with a multiplicity of orms,

requiring pallets only and at the same time, produces blocks of uniform density and structure free from lines of cleavage.

My invention is not limited to the embodiment hereinbefore described and illustrated in the accompanying drawings, but may be embodied in various forms within the nature of the invention and the scope of the following claims.

What I claim is 1. In a machine for tamping plastic materials, the combination of a frame, a molding box secured thereon but not attached thereto, a plurality of depending racks secured to the base of said molding box, a shaft mounted on one side of the frame and provided with a plurality of segment pinions meshing respectively with said depending racks, a lever secured on one end of said shaft whereby said shaft is turned to lift and to drop said molding box on said frame, said lever being adjustable on the end of said shaft to lengthen and shorten the same, and a wheel mounted eccentrically with respect to said shaft and provided with laterally extending rolls or projections to successively engage and disengage said lever intermittently to operate the same when said wheel is rotated.

2. In a machine for tamping plastic materials, the combination of a frame, a molding box mounted thereon, a plurality of depending racks secured to the base of said molding box, a shaft mounted under said molding box and provided with a plurality of segment pinions meshing respectively with said depending racks, a lever secured is turned to lift said molding box in said frame and permit it to drop, said lever being adjustable on the end of said shaft to regulate the amount of the lift and drop of said molding box, and means adapted to successively engage and disengage said arm intermittently to turn said shaft to lift and to permit to drop the said molding box on said frame.

3. In a machine for tamping plastic materials, the combination of a mold box, a toothed member depending therefrom, a shaft mounted below said molding box having a segmental toothed portion meshing with said depending toothed member, means at one end of said shaft for operating the same to lift said mold box and ermit it to drop, and cooperating means or causing successive and intermittent actuations of said last mentioned means.

In testimony whereof, I hereunto set my hand, in the presence of two subscribing witnesses, this the 21st day of February,

FRANK B. WILLIAMS. Witnesses:

CHARLES F. RICHARDSON, E. F. MIAL. 

